Fima, P., and L. I. Vainerman. “A Locally Compact Quantum Group of Triangular Matrices”. Ukrains’kyi Matematychnyi Zhurnal 60, no. 4 (April 25, 2008): 564–576. Accessed April 26, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/3176.